DNA sequencing and personalised medicine

Question 1

Compare Sanger sequencing with Next generation sequencing

Answer 1

SS:
-amplification of region with nucleoside terminators
-sequence of specific region of interest (max 400bp)
-££
NGS
-fragmentation, sequencing and mapping of reads
-sequence of genome/transcriptome /translatome/microbiome
-££££

Question 2

Evaluate the use of SS

Answer 2

BENEFITS:
-quick 
-gives specific sequence
LIMITATION: 
-cant easily multiplex
-ideally between 250-1000bp

Question 3

Evaluate NGS

Answer 3

BENEFITS:
-massively multiplex
-multiple library preparations
LIMITATIONS:
-cost
-time
-read-depth
-data overload
-library biases

Question 4

How are DNA sequencing technologies used to determine molecular basis of monogenic diseases

Answer 4

• PCR for diagnosis (CF)
• Preimplantation diagnosis for IVF embryos (PCR specific genes)
• Mitochondrial transfer (3 parent babies